Support parsing Oracle CREATE OR sql

[FlyingZC]

Background

Hi community, This issue is for #26878.

ShardingSphere parser engine helps users parse a SQL to get the AST (Abstract Syntax Tree) and visit this tree to get SQLStatement (Java Object). Currently, we are planning to enhance the support for Oracle SQL parsing in ShardingSphere.

More details: https://shardingsphere.apache.org/document/current/en/reference/sharding/parse/

Task

This issue is to support more oracle sql parse, as follows:

CREATE OR REPLACE TRIGGER dept_set_null
  AFTER DELETE OR UPDATE OF Deptno ON dept
  FOR EACH ROW

  -- Before row is deleted from dept or primary key (DEPTNO) of dept is updated,
  -- set all corresponding dependent foreign key values in emp to NULL:

BEGIN
  IF UPDATING AND :OLD.Deptno != :NEW.Deptno OR DELETING THEN
    UPDATE emp SET emp.Deptno = NULL
    WHERE emp.Deptno = :OLD.Deptno;
  END IF;
END;

CREATE OR REPLACE TRIGGER drop_trigger
  BEFORE DROP ON hr.SCHEMA
  BEGIN
    RAISE_APPLICATION_ERROR (
      num => -20000,
      msg => 'Cannot drop object');
  END;

CREATE OR REPLACE TRIGGER employees_tr
  AFTER INSERT ON employees
  FOR EACH ROW
BEGIN
  -- When remote database is unavailable, compilation fails here:
  INSERT INTO employees@remote (
    employee_id, first_name, last_name, email, hire_date, job_id
  ) 
  VALUES (
    99, 'Jane', 'Doe', 'jane.doe@example.com', SYSDATE, 'ST_MAN'
  );
EXCEPTION
  WHEN OTHERS THEN
    INSERT INTO emp_log (Emp_id, Log_date, New_salary, Action)
      VALUES (99, SYSDATE, NULL, 'Could not insert');
    RAISE;
END;

CREATE OR REPLACE TRIGGER employees_tr
  AFTER INSERT ON employees
  FOR EACH ROW
BEGIN
  insert_row_proc;
END;

CREATE OR REPLACE TRIGGER log_salary_increase
  AFTER UPDATE OF salary ON employees
  FOR EACH ROW
BEGIN
  INSERT INTO Emp_log (Emp_id, Log_date, New_salary, Action)
  VALUES (:NEW.employee_id, SYSDATE, :NEW.salary, 'New Salary');
END;

Process

1. First confirm that this is a correct oracle sql syntax, if not please ignore;
2. Compare SQL definitions in Oficial SQL Doc and ShardingSphere SQL Doc;
3. If there is any difference in ShardingSphere SQL Doc, please correct them by referring to the Official SQL Doc;
4. Run mvn install the current_file_module;
5. Check whether there are any exceptions. If indeed, please fix them. (Especially xxxVisitor.class);
6. Add new corresponding SQL case in SQL Cases and expected parsed result in Expected Statment XML;
7. Run SQLParserParameterizedTest to make sure no exceptions.

Relevant Skills

1. Master JAVA language
2. Have a basic understanding of Antlr g4 file
3. Be familiar with Oracle SQLs

[github-actions[bot]]

There hasn't been any activity on this issue recently, and in order to prioritize active issues, it will be marked as stale.

[github-actions[bot]]

There hasn't been any activity on this issue recently, and in order to prioritize active issues, it will be marked as stale.